1 //
2 // Copyright (C) 2014 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16
17 #include "shill/protobuf_lite_streams.h"
18
19 #include <fcntl.h>
20 #include <sys/types.h>
21
22 #include <base/files/file_util.h>
23 #include <base/posix/eintr_wrapper.h>
24
25 using google::protobuf::io::CopyingInputStream;
26 using google::protobuf::io::CopyingInputStreamAdaptor;
27 using std::string;
28
29 namespace shill {
30
protobuf_lite_file_input_stream(const string & file_path)31 CopyingInputStreamAdaptor* protobuf_lite_file_input_stream(
32 const string& file_path) {
33 int fd = HANDLE_EINTR(open(file_path.c_str(), O_RDONLY));
34 if (fd == -1) {
35 PLOG(ERROR) << __func__ << ": "
36 << "Could not load protobuf file [" << file_path << "] ";
37 return nullptr;
38 }
39
40 auto* file_stream(new ProtobufLiteCopyingFileInputStream(fd));
41 auto* adaptor(new CopyingInputStreamAdaptor(
42 static_cast<CopyingInputStream*>(file_stream)));
43 // Pass ownership of |file_stream|.
44 adaptor->SetOwnsCopyingStream(true);
45 return adaptor;
46 }
47
48
ProtobufLiteCopyingFileInputStream(int fd)49 ProtobufLiteCopyingFileInputStream::ProtobufLiteCopyingFileInputStream(int fd)
50 : fd_(fd),
51 scoped_fd_closer_(fd_),
52 previous_seek_failed_(false) {}
53
~ProtobufLiteCopyingFileInputStream()54 ProtobufLiteCopyingFileInputStream::~ProtobufLiteCopyingFileInputStream() {}
55
Read(void * buffer,int size)56 int ProtobufLiteCopyingFileInputStream::Read(void* buffer, int size) {
57 return HANDLE_EINTR(read(fd_, buffer, size));
58 }
59
Skip(int count)60 int ProtobufLiteCopyingFileInputStream::Skip(int count) {
61 if (!previous_seek_failed_ &&
62 lseek(fd_, count, SEEK_CUR) != static_cast<off_t>(-1)) {
63 // seek succeeded.
64 return count;
65 }
66 // Let's not attempt to seek again later.
67 previous_seek_failed_ = true;
68 return CopyingInputStream::Skip(count);
69 }
70
71 } // namespace shill
72